Contact stems for bulbs,plugs and the like



Aug. 25, 1910 BUSTAMANT? 3,525,899

CONTACT STEMS FOR BULBS, PLUGS AND THE LIKE Original Filed 001:. 28'. 1964 2 SheetsSheet 1 INVENTOR C FOBHMPBUSfl/W'Ifi %M,@/MM ATTORNEYS 25, 1910 c. R. p. BUSTAMANTE 3,525,899

CONTACT STEMS FOR BULBS, PLUGS AND THELIKE Original Filed Oct. 28, 1964 2 sheets-sheet 2 INVEN'I'OR 01305: mfZBus/wmzvm 97m ATTORNEYS United States Patent 3,525,899 CONTACT STEMS FOR BULBS, PLUGS AND THE LIKE Carlos Roberto P. Bustamante, 4a C.P. 40, Santa Ana, El Salvador Original application Oct. 28, 1964, Ser. No. 407,100. Divided and this application Feb. 17, 1967, Ser. No.

Int. Cl. H01j 5/48, 5/50 U.S. Cl. 313-318 4 Claims ABSTRACT OF THE DISCLOSURE BRIEF DESCRIPTION OF THE INVENTION- The present invention relates to bulbs, plugs and similar devices and, in particular, to novel stems or prongs utilized on these devices for mounting and retaining the devices in the slots of continuous electrical outlets.

Many types of bulbs and plugs are adapted to be used with continuous electrical outlets. However, heretofore, these bulbs and plugs have created certain problems which are solved by the unique stern of the present invention. For example, the use of bulbs with threaded bases,'requires that the continuous electrical outlets have a specific number of individual sockets thereby limiting the number of bulbs which can the used and the position of these bulbs on the outlet.

This is a division of application Ser. N0. 407,100, filed Oct. 28, 1964 now Pat. No. 3,341,803.

In a common, inexpensive type of continuous electrical outlet, it has been proposed to provide electrical plugs with sharp prongs that will pierce ordinary household extension cord. This is objectionable however, since multiple piercings can fracture the Wires in the cord, while removal of the plug will leave an unsightly area in the cord, having exposed wires and inviting short circuits.

There is thus a clearly demonstrated need in the art for vast improvements in the field of combined electrical conduits-outlets of a flexible and continuous nature and the type of stems utilized on the bulbs and plugs used in these outlets.

It is therefore a principal object of this invention to provide an improved flexible continuous electrical conduit-outlet that is not subject to the defects of prior art structures.

It is another object of this invention to provide a flexible continuous electrical conduit-outlet that is not limited or restricted by the location of sockets and outlet openings therein.

It is a further object of this invention to provide a con tinuous electrical conduit-outlet (hereinafter referred to simply as a conduit) that is truly flexible and susceptible to a variety of artistic adaptions, and yet will be of economical cost and amendable to mass production.

It is a still further object of this invention to provide a novel baseless electric lamp and outlet plug having terminal contact portions that are eminently suitable for use with the new conduit-outlet of this invention.

Still another object of this invention is to provide a rnulti-outlet system comprising a plurality of baseless "ice lamps and outlet plugs having wedge-shaped stem press portions at one end and supported by their stem press portions in side-by-side relation in a continuous conductor for free sliding movement therethrough.

Other objects of this invention, together with an appreciation for the advantages thereof, will become increasing apparent as this description proceeds.

Broadly stated, the objects of this invention are accomplished by providing a central strip of insulating material which is joined with two electrically conductive strips connected in turn with outer metal strips which provide electrical contacts of opposite polarity. The electrically conductive members are prepared from an electrically conductive interior web which is sealed or laminated within an insulating material, for example, by sandwiching the electrically conductive web between two plastic insulating layers. The central insulating strip may also be of plastic and is attached by adhesive welding, etc. in abutting relationship to the electrically conductive strips. The metal strips are attached in any suitable manner to the outside ends of the electrically conductive strips, such that the strips are in electrical contact with the conductive webs. The assembly is then formed into a suitable enclosing shape, defining a longitudinal slit, and may desirably be provided with transverse slits to provide flexibility and permit dividing into a number of flexible portions that will each act as a separate bulb or plug receiving electrical socket. It is also desirable to provide wedge shaped insulating members to insure that the electrically conductive metal strips do not accidentally contact one another when the conduit is subjected to compression. A bulb and plug, each having a wedge shaped bottom contact portion are also provided to permit insertion between the electrically conductive metal members and provide a novel electrical socket-outlet concept.

The assembled electrical conduit is adapted to be used with various electrical connections, bulbs, etc., such as a group of lamps, plugs or other similar type electric devices, formed with protruding stem press portions from which project the terminal contacts of the lamp. Such devices will be slidably supported by their stem press portions in side-by-side relation within the longitudinal slit for free sliding movement therethrough. According to a further aspect of the invention, the stem press portion of each lamp or plug is wedge-shaped so that each lamp or plug may be inserted in the longitudinal slit, with the terminal contacts of the lamp or plug enclosed within the conduit such that the edges of the longitudinal slit elastically grip the stern press portion with suflicient force to support the lamp or plug in place in the conduit.

Turning now to the drawings in which the same or similar reference numerals have been used to denote similar parts throughout the several figures:

FIG. 1 is broken out pictorial view, partly in section, showing the arrangement of parts prior to assembly;

FIG. 2 is a pictorial view, partly in section and similar to FIG. 1, but showing the parts in assembled position;

FIG. 3 is a pictorial view showing the arrangement of parts after a suitable tube forming operation;

FIG. 4 is a pictorial view, showing a novel separator that has been developed according to the invention for use therewith;

FIG. 5 is an end view of the device of the invention, partly in section, and showing a bulb developed according to the invention for use therewith;

FIG. 6 is a schematic diagram illustrating a method of supporting the structure according to the invention for illuminating uses;

FIG. 7 is an embodiment, similar to FIG. 4, but illustrative of a different crosssectional shape that the invention may take, and further showing an electrical plug that has been developed according to the invention for use therewith;

FIG. 8 is another embodiment similar to FIGS. 4 and 7, but illustrating a further cross-sectional shape that may be utilized according to the invention;

FIG. 9 is a perspective view of a light bulb of the present invention with portions broken away for illustrative purposes; and

FIG. 10 is a perspective View of an electrical plug of the present invention.

In the drawings, there is shown a tubular conduit in which lamps, plugs and the like are slidably mounted. The conduit is formed of a suitable elastic or synthetic material and it is provided with a longitudinal slit extending the full length thereof. This slit is adapted to receive the flattened sides of the stem press of each lamp or plug which is forcibly inserted with the outer end of the stem press and the wire terminal contacts positioned within the slit edges of the tubular conduit which define the slit to thereby spring apart such edges. The sprung apart edges thus form a conduit and are thereby caused to elastically grip the stem press of each individual lamp or plug with suflicient force to hold them in substantial sideby-side row alignment if desired within the conduit while permitting sliding movement of the lamp therethrough. However, the elastic or spring-like engagement of the longitudinal edges of the slit serves to lock the lamp or plug in place in the conduit against easy withdrawal. In this manner, the terminal contacts of each lamp or plug are properly aligned with the electric current supply contacts of the slit edges or continuous socket-portion in which they are inserted so as to insure the proper contact of the terminal wire contacts with the electrically conductive socket contacts.

It will thus be understood that the conduits described may be constructed of any length and in any desired cross section which would provide for the proper disposition of the bulbs, plugs, and the like.

Turning now to the drawings, FIG. 1 shows the first stage of manufacture wherein a central strip 10 of insulating material *(plastic, etc.) is joined with two electrically conductive strips 12 and 14 followed by connection with outer metal contact strips 16 and 18. The electrically conductive members 12 and 14 are prepared from an electrically conductive interior web 22 (copper or aluminum wire, etc.) which is sealed or laminated within an insulating material, for example, by sandwiching the electrically conductive web between two plastic insulating layers. The member 10 may also be of plastic and is attached by adhesive welding, or the like in abutting relationship to the electrically conductive strips 12 and 14 (see FIG. 2). The metal strips 16 and 18 are attached in any suitable manner to the outside ends of the electrically conductive strips 12 and 14 as shown in FIG. 2, such that the strips 16 and 18 are in electrical contact with the webs 22.

As shown in FIG. 3, the assembly of FIG. 2 is formed into a tubular shape A and is preferably provided with slits at 24 to provide flexibility and divide the tube A into a number of flexible portions that will each act as a separate bulb receiving electrical socket. The electrical contact providing metal strips 16 and 18 of the tube shaped conduit A in FIG. 3 are prevented from coming together and creating a short circuit due to the wedge shaped insulating members 30 which are provided with a notch to be entered into the opening 28 (see FIG. 4).

The assembled electrical conduit A is adapted to be used with electrical connections, bulbs, plugs and the like such as the bulb 40 shown in FIG. 5 which has wedge shaped bottom contact portion 42 to permit the bulb to be inserted between the metal members 16 and 18 at the opening 28 (see FIGS. 3 and 4). FIGS. 7 and 8 show that the conduit A can also have other cross sectional con- 4 figurations such as at B and C. It is thus clear that the present conduit may be of any convenient shape.

The conduit A may be provided with a number of apertures, such as the transverse apertures 11 or the longitudinal apertures 13 for securing the conduit to various supports. For example, simple securing devices, such as screws or bolts in combination with the apertures 11 may be used to fasten the conduit to a suitable support. By any suitable means, the outlet may be secured to a support or wall in any desired position, such as a horizontal position or a vertical position as shown in FIG. 6.

In FIG. 6, the mounting illustrated permits the invention to be hung between suitable supports, in any desired location. As shown, a rope, cable, wire or the like 63, composed of any suitable or proper material, may be passed through the aperture 13 provided in the conduit member 10 to support the conduit.

Referring now to the separators 30, it will be recognized that any desired number of these outwardly extending separators may be employed in the slit 28 for spacing the conduit sections 12-16 and 14-18 apart at their front edges. The separator extends across the slit 28 of the conduit and is held in place by means of the notch 32. Each separator is provided, at its outer end with at least one curved edge, so that no obstruction will be offered thereto when being inserted between the conduit sections. The dimensions of the separator are also desirable for the quick and easy insertion of the bulb 40 or plug 50.

Turning now to the bulb 40, there will be seen the usual lead in wires through which the current is carried into the interior of the lamp to the filament. The lead wires extend from the inside of the glass envelope out through the bottom of the lamp through a wedge shaped section 42 of glass which is formed during the normal sealing operation by flattening out a section of the glass envelope just below the spherical portion of the envelope. The Wire leads of the illustrated embodiment are then bent out at 44 and 46 on either side of the Wedge shaped section 42 in such a manner as to cause the wire to lie snugly adjacent to the flattened glass but yet protrude therefrom to a sufficient extent to permit the making of a good electrical contact between the wire and the electrically conductive metal members 16 and 18 which will contact both flattened sides of the wedge shaped glass member. It is, of course, readily apparent that these contact leads might be positioned somewhat diflerently to obtain the same result particularly if the socket opening 28 defined by the members 16 and 18 were to be modified accordingly. The other remaining component parts of the lamp are for the most part the same as those normally used in the prior art. The two wire conductors lead to the filament which is electrically connected and secured to each of the wires at their inner end.

The lamp of this invention as shown in the drawings has two distinctive features, the one being that it has entirely eliminated the usual threaded brass base which is important from the standpoint of cost in saving material, but also saves some costly processing steps.

Referring now to the plug 50 shown in FIG. 7, it will be recognized that the structure thereof is similar for the most part to those normally used in the prior art. However, as with the bulb 40, the usual wire leads terminate in a wedge shaped portion 52 of any suitable insulating material such that they lie snugly adjacent thereto, but yet protrude therefrom to a suflicient extent to permit the making of good electrical contact between the wire leads and the metal members 16 and 18.

In accomplishing its objectives, it will be understood that the conduit forming the object of this invention will have very numerous applications in the art. For example, owing to the flexibility of the conduit, it is easy to understand that it may be straight, curved or inclined in any position, such that with this device, various combinations can be made and beautiful luminous effects can be obtained. Moreover, the present conduit can be substituted for various electrical conduits now in use which are subject to defects and objections previously noted.

It should therefore be understood that the present invention may be subject to various changes or modifications that will be apparent to those skilled in the art, without departing from the spirit of this invention.

For example, various plastic materials, including synthetic resins and glass or ceramics, can obviously be substituted for the several insulating materials shown in the drawing. It is also contemplated that the elements shown may be formed from plastic materials of divergent chemical origins, i.e., different synthetic resins or from divergent physical origins, i.e., from granular, fibrous or other particulate materials, as well as from resin sheet or liquid form resinous materials.

It is moreover within the contemplation of this inven tion that the several electrically conductive materials may have various forms. Thus, the metal contacts 16 and 18 may be replaced by any substituents which will provide the desired electrically conductive result. The form shown is, however, preferred. It is also recognized that the electrically conductive webs may be replaced by materials that will be found to act as equivalents. Presently it is preferred that the conduit contains electrically conductive webs formed from interlaced fibers of electrically conductive materials, including the various metals and alloys. By interlaced is meant the products formed by textile orientation processes such as carding, lapping, drawing, weaving, knitting, felting, and the like. The web or mesh like products thus formed may also be secured or bonded in various ways. For example, is a loosely woven or cross lapped product is employed, it may be desirable to coalesce, weld, or otherwise secure it at the junction.

Further, the invention may be subjected to some obvious physical modifications. Thus, While the strip material is shown having a substantially T-shaped configuration, permitting mounting of the invention according to embodiments using the apertures 11 or 13, it will be understood that a simpler rectangular cross-section may also be employed if desired.

Accordingly, this disclosure should only be considered as illustrative of the invention, and the invention should only be limited to the scope of the appended claims.

What is claimed is:

1. An incandescent lamp comprising a glass envelope, 3. light source enclosed in said envelope, :1 pair of electrical lead wires, a filamentous conductor connecting the ends of said lead wires within said envelope, a projecting stem press portion formed at the fused junction of said glass envelope, said stem portion having an intermediate portion with planar side surfaces, said stem portion having an enlarged terminal wedge-shaped portion which facilitates insertion of the stern into a socket, said intermediate portion being located between said terminal wedge-shaped portion and said envelope, and the ends of said lead wires projecting from said glass envelope through said stem press portion and presenting exposed contacts on said planar side surfaces which terminate short of said enlarged terminal wedge-shaped portion.

2. In the incandescent lamp of claim 1, the planar side surfaces being parallel with respect to each other, and the terminal wedge-shaped portion having outwardly extending converging planar side surfaces.

3. An electrical plug comprising a plug element of insulating material, a pair of electrical lead wires adapted to be connected to an electrical energy dissipating device, a projecting stem press portion joined to said plug element, said stern having an intermediate portion with planar side surfaces, said stem portion having an enlarged terminal wedge-shaped portion adapted to facilitate the entry of said stem into a socket, said intermediate portion being located between said terminal wedge-shaped portion and said plug element, the ends of said electrical lead wires projecting from said insulating envelope through said stem press portion and presenting exposed contacts on said planar side surfaces which terminate short of said enlarged terminal wedge-shaped portion.

4. In the electrical plug of claim 3, the planar side surfaces being parallel with respect to each other, and the terminal wedge-shaped portion having outwardly extending converging planar side surfaces.

References Cited UNITED STATES PATENTS 2,448,937 9/ 1948 Walter 3l3--318 X 2,699,659 1/1955 Haas 3l3318 X 3,016,727 1/1962 Vanden Boom et a1. 313318 X 3,093,768 6/1963 Ayres 313318 3,345,526 10/1967 Wright 313-318 X 3,407,054 10/1968 Ose et al. 313---3 18 X FOREIGN PATENTS 901,989 7/1962 Great Britain.

JOHN W. HUCKERT, Primary Examiner A. J. JAMES, Assistant Examiner US. Cl. X.R. 

